Groverton Mass Transit Authority: Constructing the county's new expres

Question

CR ASSUMPTION SERIES: 3) Groverton Mass Transit Authority

Groverton Mass Transit Authority: Constructing the county's new express bus service lanes will require the closure of several main traffic arteries for at least a month. Construction work could be done primarily overnight with less traffic disruption; however, overnight labor costs are considerably higher. Therefore to minimize the economic impact to our residents, the authority recommends that construction occur during normal business hours.

The recommendation made by the Groverton Mass Transit Authority to construct the express bus service lanes during normal business hours assumes which of the following?

A The majority of Groverton's residents would be able to commute with minimal disruption while the express bus service lanes are under construction.

B Upon completion, the new express bus service lanes will likely be used by many of Groverton's residents.

C Whether overnight or during regular business hours, construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers.

D The economic cost of any time lost due to construction of the express bus service lanes during regular business hours won't exceed the economic cost associated with overnight construction.

E The economic value of the express bus service lanes to Groverton residents would not surpass the costs associated with overnight construction.

48 Hour Window Answer & Explanation Window  
 Earn KUDOS!  Have your explanations evaluated to help boost your learning. Post your reasoning why the answer you chose is correct, and why the other 4 options are incorrect within 48 hours of this post.

◀ CR ASSUMPTION SERIES: Question 2) Violent Forms of Robbery

▶ CR EVALUATION SERIES: Question 1) The Berringer Motorcycle Co.

sun01 · Answer

The flow of argument is as under:

1. Regular business-time construction will bring closure of several traffic lanes, leading to troubles for residents.

2. construction can be done in night, but it involves huge overnight labor cost, that is to borne by the residents.

So, in the economic interest of the residents of the town, it is better to go for regular-time construction.

With this argument structure, only D and E make sense.

initially i went for E.

Reason for selecting E: economic value of the lanes constructed will not be sufficient for the to over the overnight construction cost .

Problem with D is the phrase:  The economic cost of any time lost due to construction of

if the phrase had been  economic cost of the lost business hour   due to regular time construction, it would have made more sense.

PrakharGMAT · Answer

Hi Experts /  chetan2u  /  daagh ,

Initially went with C as didn't read D properly.
After careful analysis I totally agree with D as OA but somehow I am still not able to eliminate C.

According to me C can also be an assumption.

Eg- Lets total work will take 100 hours. If Day worker cost $10 per hr and Night crew charge $20
Day Labor charge= 100x 10= $1100
Night labor charge= 100x20= $2000
Clearly, using day labor is good.

But, what if day labor take 201 hrs to complete. Then, 201x 10= $2010
In this scenario, using night labor will be good

So, to strengthen the argument we need to ASSUME that total no of working hours will be same.

C->Whether overnight or during regular business hours, construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers.

I just observed, this option says WEATHER ( Is it a trap)
It says, the no of hours might be same or might be not...!!
I think EMPOWER trying to blend weakening and EVALUATE questions..

is my reasoning correct...??
Please assist

chetan2u · Answer

Hi,

firstly we got to understand what is asked, so lets see that:-  
 The recommendation made by the Groverton Mass Transit Authority to construct the express bus service lanes during normal business hours assumes which of the following?

so what is the recommendation?
Therefore to minimize the economic impact to our residents, the authority recommends that construction occur during normal business hours. 
Therefore we have to have our answer that has something to do with the ECONOMIC ASPECT

Since you are clear on D as OA, I will leave it and answer '' why C should not be the answer?''  
 Ⓒ Whether overnight or during regular business hours, construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers.
As we have seen earlier that the recommendations are on economic aspect and it has been clearly given that labor costs are higher. The labor costs higher could be because of more labor or because of working in night. 
So he explicitly mentions on labor cost increase (---- however, overnight labor costs are considerably higher--) , therefore it cannot be assumption. And we are not concerned about time.

sun01 · Answer

Dear chetan2u

Could you shed some light on D? I have some doubts on D. mentioned in my previous post.

Thanks

EMPOWERgmatVerbal · Answer

Official Explanation

Question Type  : Assumption
  Boil It Down   (Simplified & Abbreviated Summary of the Prompt): Overnight construction costs higher -> Daytime construction lower economic impact
  Missing Information (assumption)  : Groverton Transit Authority’s argument makes a remarkable oversight in considering economic impact: what about the economic impact attributable to lost productivity as a result of daytime construction? What if were to turn out that the economic damage from construction during normal business hours would far eclipse the cost associated with paying a crew for overnight construction?

Goal  :  Find the option that contains required missing information.

Note: The Opposite Test – Since by definition an assumption is a piece of missing information required for the argument to work, if we take the opposite of a valid assumption the argument will collapse. Therefore, we can use the Opposite Test with the options. Just take the logical opposite of the option and ask: does the argument collapse? If not, the option is wrong. If yes, it’s the correct option. Note that we’d only need to apply the Opposite Test to options that are in contention. There’s no need to waste time examining options that are obviously non-essential.

Let’s see which option best achieves the goal:

Ⓐ The majority of Groverton's residents would be able to commute with minimal disruption while the express bus service lanes are under construction.
Minimal disruption to even a majority of Groverton’s residents is not something the logic of this argument requires. Applying the Opposite Test: There could be more than minimal disruption to a majority of Groverton’s residents, but the Authority’s argument could still stand.

Ⓑ Upon completion, the new express bus service lanes will likely be used by many of Groverton's residents.
End use of the lanes is not actually relevant to the focus of this argument at all (the construction phase). What happens after construction is irrelevant to the question of whether the lanes should be constructed overnight or during regular business hours.

ⒸWhether overnight or during regular business hours, construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers.
This is the runner-up option. Here’s the scoop on why we can scrap this option: Groverton Transit Authority’s argument doesn’t hinge on whether the construction duration, and the number of workers are the same. They could vary and that argument still holds. Since this option isn’t essential to the reasoning we can get rid of it.

ⒹThe economic cost of any time lost due to construction of the express bus service lanes during regular business hours won’t exceed the economic cost associated with overnight construction.
Now here’s the option the argument requires for the logic to hold. Since the rationale to choose the normal business hour option is economic impact, the Authority’s argument absolutely requires that the economic impact of the lost time from the closure of several main traffic arteries not exceed the economic impact to foot the more expensive bill of overnight construction. Applying the Opposite Test here: The economic cost of any lost time from regular business hour construction would exceed the cost of overnight construction. In other words, what happens to the argument if the economic cost of daytime construction were to exceed the added expense of overnight construction? The argument collapses.

Ⓔ The economic value of the express bus service lanes to Groverton residents would not surpass the costs associated with overnight construction.
This option delves into what kind of economic value could be gained post-construction, which is Out of Focus. On top of that, this option presents something that the argument might even assume the exact opposite of.

Look what happens when we take the opposite of this option: The economic value to Groverton residents of the express bus service lanes would surpass the costs associated with overnight construction. Notice how the opposite of this option actually seems to go along with the argument rather than destroy it? That means this option does the opposite of what we need. Ultimately though, this option is irrelevant to the consideration of overnight construction or regular business hour construction since with either, the economic value of the utility of the express bus lanes could exceed the construction costs.

◀ CR ASSUMPTION SERIES: Question 2) Violent Forms of Robbery

▶ CR EVALUATION SERIES: Question 1) The Berringer Motorcycle Co.

chetan2u · Answer

Hi,

lets see the choice D and E...
  Both are relating an economic aspect to same issue: the costs involved in night construction
1) D talks of economic cost lost due to extra time spent by residents during regular business hours with the costs in night construction..
2) E talks of the general economic value not during this period of construction but with what is gained in future

For understanding which should be the answer, lets see what is the recommendation doing..
In the para, we are comparing extra time during regular business to extra cost in ni constr..

D compares the two things correctly, so as to choose day constr over ni constr..
E, I would say is too extreme.

NOTE:-lets try to analyze E, which ofcourse is beyond the requirement of Q.--If the over all economic value cannot surpass the construction costs, is the highway even required .

EMPOWERgmatVerbal · Answer

Hi RAHKARP27071989,

I'd be happy to help. You raise something important when you say "can be an assumption". In an Assumption question, we're not interested in what CAN be assumed, we're looking for the one option that MUST be assumed. Of these 5 options, the only one that MUST be assumed for the logic of the argument to hold is D.

With C, the construction duration, and the number of workers could vary and that argument still holds. Since this option isn’t essential to the reasoning we can get rid of it. Whereas, if we pull D away from the argument, it collapses.

In regard to your question about Evaluate questions, I think you may have misread the option. C says: " Whether overnight  or  during regular business hours , construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers." Meaning, whether Groverton chooses the overnight option or the regular business hour option, the projected construction duration, and number of workers won't vary.

PrakharGMAT · Answer

EMPOWERgmatMax ,
You were right, I misread option C and took it like an evaluate option.

chetan2u / EMPOWERgmatMax ,

Thanks alot for quick reply. I just want to ask you few more things.

But, Please help me in negating Option C.

Total Cost for Day (CD) = No of workers in Day ( WD) x Total No of Hours in Day ( HD ) x Labor charge in Day ( LD)
Total Cost for Night (CN) = No of workers in Night ( WN) x Total No of Hours in Night ( HN ) x Labor charge in Night ( LN)

According to Option C--> WD = WN and HD = HN
As per question stem--> LD<<< LN

This implies--> Total Cost for Day (CD) <<< Total Cost for Night (CN (Its completely an ECONOMIC ASPECT )

Behind every conclusion, we assume multiple things-

Eg-
Conclusion- Jack must have studied really hard to score 750 in GMAT to get into IVY colleges.
Assumption 1- GMAT is an exam of marks >= 750
Assumption 2- IVY colleges accept GMAT score.

In the same way-
C and D both are strengthening Conclusion.
And Hence both must be assumed

Please assist, how can we negate Option C.

EMPOWERgmatVerbal · Answer

Hi PrakharGMAT,

To your question:

Let's take a look at C again:

ⒸWhether overnight or during regular business hours, construction of the express bus service lanes is expected to take the same amount of time and require the same number of workers.

The opposite of this assumption is that construction of the express bus service lanes is  NOT  expected to take the same amount of time and require the same number of workers. Taking the opposite of option C leaves open the possibility that it could take longer overnight, or less time overnight since "not the same amount of time" could be anything other than the same.

Additionally, the same governing logic applies to the number of workers: the opposite of this assumption in that regard would mean that overnight construction could require fewer workers, or even a greater number of workers. Essentially, the opposite of this option gives us useless and uninterpretable information that by its own ambiguity renders it of no consequence to the argument.

Since this option isn’t essential to the reasoning we can get rid of it.

Bigger GMAT Picture: 
You mentioned " C and D both are strengthening Conclusion. And Hence both must be assumed ". That raises a critical issue. We don't measure the utility of an assumption by whether it helps support an argument. Assumptions are gauged as to whether they are REQUIRED for the logic to hold. If an argument survives just fine without a piece of information, then that information is NOT assumed. On the other hand, if an argument collapses if the opposite of a possible assumption is taken, then that piece of information IS required. That's what an assumption is.

To put it another way for good measure: an assumption is a piece of information that without, the argument dies.

PrakharGMAT · Answer

Thank you  EMPOWERgmatMax

daboo343 · Answer

Clearly D, The economic cost of any time lost due to construction of the express bus service lanes during regular business hours won't exceed the economic cost associated with overnight construction, is the assumption
if we negate this it will shatter the conclusion

VerbalBot · Answer

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Groverton Mass Transit Authority: Constructing the county's new expres

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